\section{Missing Weather File Data}\label{missing-weather-file-data}

The weather description of data contains ``missing'' descriptors, a new concept not introduced previously in our IDD conventions. In this case, it will be processed as though those values are ``missing'' in the weather conversions and/or EnergyPlus weather processing. This may not always be desirable though EnergyPlus will fill in ``missing'' value with something ``appropriate''. Eventually, these missing values will be available through the IDD and users will be able to supply their own values or EnergyPlus will calculate those values (such as radiation and illuminance) that are not a simple value replacement. Until then, the following are used:

% table 44
\begin{longtable}[c]{p{1.83in}p{2.67in}p{1.5in}}
\caption{Missing weather replacement values \label{table:missing-weather-replacement-values}} \tabularnewline
\toprule
Data item & Supplied Value & Units \tabularnewline
\midrule
\endfirsthead

\caption[]{Missing weather replacement values} \tabularnewline
\toprule
Data item & Supplied Value & Units \tabularnewline
\midrule
\endhead

Dry-bulb Temperature & 6 & C \tabularnewline
Dewpoint Temperature & 3 & C \tabularnewline
Relative Humidity & 50 & \% \tabularnewline
Atmospheric Pressure & Standard** Barometric Pressure (altitude based) & Pa \tabularnewline
Wind Speed & 2.5 & m/s \tabularnewline
Wind Direction & 180 & Deg \tabularnewline
Total Sky Cover & 5 & (tenths) \tabularnewline
Opaque Sky Cover & 5 & (tenths) \tabularnewline
Visibility & 777.7 & Km \tabularnewline
Ceiling Height & 77777 & m \tabularnewline
Precipitable Water & 0 & Mm \tabularnewline
Aerosol Optical Depth & 0 & Broadband turbidity \tabularnewline
Snow Depth & 0 & Cm \tabularnewline
Days Since Last Snow & 88 & Days \tabularnewline
Radiation Values (Direct/Diffuse) & 0.0 & Wh/m2 \tabularnewline
Illuminance Values & 0.0 & lux (or CD/m2) \tabularnewline
\bottomrule
\end{longtable}

**Standard Barometric pressure based on location elevation is taken from ASHRAE 2001 Handbook of Fundamentals, Page 6.1 \& 2.
